Question about magnets.

I figured with how big the internet is, there would be an entire forum on magnets somewhere out there for me to ask my question but it turns out, if it does exist, I couldn't find it. So I figured you guys would be just as good, if not better

I'm building an object that has 2 halves that are to be held together by magnets. What I couldn't figure out was this:

The ones I was looking at was http://unitednuclear.com/m0.250r.jpg [Broken] and http://unitednuclear.com/m0.500g.jpg [Broken]. I was thinking about whether to put a cylindrical magnet on both sides, or a ring magnet on one side and the cylindrical magnet on the other (which would fit inside the ring when closed). Regardless of the fact that the ring will stabilize the halves in one dimension, which configuration will have the greatest magnetic pull assuming they're of the same compound grade?